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101.
102.
A. Pasquali 《Annali di Matematica Pura ed Applicata》1969,82(1):35-47
Summary In this paper, we study a class of iterative processes of the type yn+1
=Tnyn, which approximate the iterative processes xn+1
=Txn, where T and Tn are more general operators than contractions in a metric space.
Entrata in Redazione il 27 marzo 1969.
Istituto Matematico ?U. Dini?, Università degli Studi di Firenze, Viale Morgagni 67/a Firenze. Lavoro eseguito in relazione al Contratto No 115.3050.0.5189 del Comitato per la Matematica del C.N.R. nel corso dell'anno accademico 1968–69. 相似文献
Entrata in Redazione il 27 marzo 1969.
Istituto Matematico ?U. Dini?, Università degli Studi di Firenze, Viale Morgagni 67/a Firenze. Lavoro eseguito in relazione al Contratto No 115.3050.0.5189 del Comitato per la Matematica del C.N.R. nel corso dell'anno accademico 1968–69. 相似文献
103.
E. Geraci U. Abbondanno L. Bardelli S. Barlini M. Bini M. Bruno F. Cannata G. Casini M. Chiari M. D'Agostino J. De Sanctis A. Giussani F. Gramegna V. L. Kravchuk A. L. Lanchais P. Marini A. Moroni A. Nannini A. Olmi A. Ordine G. Pasquali S. Piantelli G. Poggi G. Vannini 《The European physical journal. Special topics》2007,150(1):21-22
Symmetry energy is a key quantity in the study of the equation of state of asymmetric nuclear
matter. Heavy ion collisions at low and intermediate energies, performed at Laboratori Nazionali
di Legnaro and Laboratori Nazionali del Sud, can be used to extract information on the symmetry
energy coefficient Csym, which is currently poorly known but relevant both for astrophysics and
for deeper knowledge of the structure of exotic nuclei. 相似文献
104.
A model of semiflexible bead-rod chain with anisotropic friction can mimic closely the hydrodynamics of a slender filament. We present an efficient algorithm for Brownian dynamics simulations of this model with configuration dependent anisotropic bead friction coefficients. The algorithm is an extension of that given previously for the case of configuration independent isotropic friction coefficients by Grassia and Hinch [J. Fluid Mech. 308, 255 (1996)]. We confirm that the algorithm yields predicted values for various equilibrium properties. We also present a stochastic algorithm for evaluation of the stress tensor, and we show that in the limit of stiff chains the algorithm recovers the results of Kirkwood and Plock [J. Chem. Phys. 24, 665 (1956)] for rigid rods with hydrodynamic interactions. 相似文献
105.
Human liver protein map: a reference database established by microsequencing and gel comparison. 总被引:2,自引:0,他引:2
D F Hochstrasser S Frutiger N Paquet A Bairoch F Ravier C Pasquali J C Sanchez J D Tissot B Bjellqvist R Vargas 《Electrophoresis》1992,13(12):992-1001
This publication establishes a reference human liver protein map obtained with immobilized pH gradients. By microsequencing, 57 spots or 42 polypeptide chains were identified. By protein map comparison and matching (liver, red blood cell and plasma sample maps), 8 additional proteins were identified. The new polypeptides and previously known proteins are listed in a table and/or labeled on the protein map, thus providing a human liver two-dimensional gel database. This reference map can be used to identify protein spots on other samples such as rectal cancer biopsies. 相似文献
106.
Plasma protein map: an update by microsequencing. 总被引:4,自引:0,他引:4
G J Hughes S Frutiger N Paquet F Ravier C Pasquali J C Sanchez R James J D Tissot B Bjellqvist D F Hochstrasser 《Electrophoresis》1992,13(9-10):707-714
The reference plasma protein map, obtained with immobilized pH gradients in the first dimension of two-dimensional electrophoresis, is presented. By microsequencing, more than 40 polypeptide chains were identified. The new polypeptides and previously known proteins are listed in a table and labeled on the protein map, thus providing an update of the human plasma two-dimensional gel database. 相似文献
107.
108.
We show that, when subjected to microwave fields, surfactant-stabilized single-walled carbon nanotubes (SWNTs) develop polarization potentials at their extremities that readily drive electrochemical reactions. In the presence of transition metal salts with high oxidation potential (e.g., FeCl3), SWNTs drive reductive condensation to metallic nanoparticles with essentially diffusion-limited kinetics in a laboratory microwave reactor. Using HAuCl4, metallic particles and sheaths deposit regioselectively at the SWNT tips, yielding novel SWNT-metal composite nanostructures. This process is shown to activate exclusively metallic SWNTs; a degree of diameter selectivity is observed using acceptors with different oxidation potentials. The reaction mechanism is shown to involve Fowler-Nordheim field emission in solution, where electric fields concentrate at the SWNT tips (attaining approximately 10(9) V/m) due to the SWNT high aspect ratio (approximately 1000) and gradient compression in the insulating surfactant monolayer. Nanotube antenna chemistry is remarkably simple and should be useful in SWNT separation and fractionation processes, while the unusual nanostructures produced could impact nanomedicine, energy harvesting, and synthetic applications. 相似文献
109.
Pasquali L Terzi F Seeber R Doyle BP Nannarone S 《The Journal of chemical physics》2008,128(13):134711
1,4-benzenedimethanethiol was chemisorbed from the vapor phase onto Au(111). The chemisorption geometry, molecular orientation, and bonding properties were studied at different degrees of surface coverage by photoelectron spectroscopy, metastable deexcitation spectroscopy, and near-edge x-ray absorption fine structure spectroscopy at the carbon K edge. Two main chemisorption regimes were identified: at low coverage the molecules adopt a flat configuration, then, as the molecular density of the first layer increases, the reduction of the available chemisorption sites induces the newly bonded molecules to assume a vertical alignment, with only one of the sulphur head groups interacting with the substrate. Experimental results were interpreted on the basis of theoretical calculations that we performed on the free molecule concerning the molecular orbitals' density of states and simulated x-ray absorption. 相似文献
110.
Spectrophotometric simultaneous determination of nitrite, nitrate and ammonium in soils by flow injection analysis 总被引:1,自引:0,他引:1
López Pasquali CE Fernández Hernando P Durand Alegría JS 《Analytica chimica acta》2007,600(1-2):177-182
A new rapid flow injection procedure for the simultaneous determination of nitrate, nitrite and ammonium in single flow injection analysis system is proposed. The procedure combines on-line reduction of nitrate to nitrite and oxidation of ammonium to nitrite with spectrophotometric detection of nitrite by using the Griess-llosvay reaction. The formed azo dye was measured at 543 nm. The influence of reagent concentration and manifold parameters were studied. Nitrite, nitrate and ammonium can be determined within the range of 0.02–1.60 μg mL−1, 0.02–1.60 μg mL−1 and 0.05–1.40 μg mL−1, respectively. R.S.D. values (n = 10) were 2.66; 1.41 and 3.58 for nitrate, nitrite and ammonium, respectively. This procedure allows the determination and speciation of inorganic nitrogen species in soils with a single injection in a simple way, and high sampling rate (18 h−1). Detection limits of 0.013, 0.046 and 0.047 μg mL−1were achieved for nitrate, nitrite and ammonium, respectively. In comparison with others methods, the proposed one is more simple, it uses as single chromogenic reagent less injection volume (250 mL in stead of 350 mL) and it has a higher sampling rate. 相似文献